Rotary pump



March 3, 1931. o. s. JOHNSON 1,795,130

' ROTARY PUMP Filed April 27. 1929 Patented Mar. 3, 1931 our s. JOHNSON, or emucns'rnn cI'zrY, NEW JERSEY ROTARY Pour Application filed April 27,

This invention relates to the valveless type [of rotary pump having a solid rotor provided with a cylindrical bore extending transversely across its axis. oft rotation, in

IS which is located a reciprocating piston, operable, when the rotor is actuated, by an ec-' centric projection extending into the cylindrical bore of the rotor from the end wall of the pump casingfg;

This type of pump is given to excessive noise, vibration, and wear, which renders the pump undesirable.

The object of my invention is to construct the elements of this general type of pump in such a manner that the attendant noise, v1-

'bration, and wear are practically eliminated.

Other advantages arising from the novel construction of a pump of this general type made in accordance with theprinciples of my invention, and the construction of the pump in'detail, will be fully disclosed hereinafter, reference being had to the accompanying drawings, of whichf I Fig. 1 is a longitudinal sectional elevation of the pump, taken on the line 11 of Fig. 2;

Fig. 2 is a transverse sectional elevation taken on the line 22, Fig. 1; and

Fig. 3 is a longitudinal sectional view of the piston.

Referring to the drawings, the pump casing is indicated at'l. This casing is provided with a longitudinally extending cylindrical bore 2, for the reception of a cylindrical rotor 3. Closure heads 4 and 5 are provided at the respective ends of the casing 1, for confining the rotor 3 within the cylindrical bore 2 of the casing.

The heads 4 and 5-aresecured to the easing 1 by means of bolts or screws 7, 7.

As shown in Fig. 1, the rotor 3 snugly fits within the bore '2, between the heads 4 and 5, but is permitted free rotation within said casing.

The rotor 3 is provided with a shaft 6, by means of which 1t may be rotated from any suitable source of power, preferably an electric motor (not shown).

A packing land 17 is provided in the head 4 to'preventt e escape of fluid from the casing 1 around the shaft 6.

1929. Serial No. 358,546.

The head 5 is provided with a circular boss 8 which is axially aligned with the shaft 6. The boss 8 is concentrically bored. as at 9, for the reception of a hardened steel bearing element 10. I I

The bearing element 10 is driven into andis thereby rigidly secured in the boss 8 and extends longitudinally of and concentrically with respect to the longitudinal axis of V the casing 1 and beyond the inner wall of the head 5 and into a counterbore 11 formed in and concentric with respect to the end of the rotor 3 opposite to that from which the shaft 6 projects, thus providing a substantial support for this end of the rotor. I The rotor 3 is also provided with a cylindrical bore 12 which extends transversely of the rotor across the axis of rotation thereof.

Reciprocally and rotatably mounted in the cylindrical bore 12 of the rotor 3 is a piston 13 having an annular groove 14 extending completel aroundits periphery intermediate of an substantially equidistant from the opposite ends of the said piston.

The rotor 3 is provided with a circular concentric openin 15 which communicates with the bore 12 an counterbore 11 of the rotor 3.

Positioned eccentric with respect to the axis ofrotation of the rotor. 3 and extending longitudinally thereof from the inner end of the bearing member 10, through the circu lar opening 15 and into the transverse bore 12 of the rotor 3 is a projection 20, the inner end of which, as shown in Figs. 1 and 20f the drawing, lies within the annular groove 14 in the reciprocating piston 13.

From the above -it will be obvious that as the rotor 3 is rotated the piston 13 will be reciprocated within the bore 12, due to the ec- H centricity of the projection 20 with respect to the axis of rotation of the rotor 3.

Due to the annular groove 14,0f the piston 13 extending completely around the piston, the piston will be permitted free rotation the bore 12.

Actual experience has proven that the piston "has a tendency to rotate within the bore and if restricted a severe pounding of the piston against the stationary projection ensues,

which creates excessive noise and objiectionable vibration in the pump.

By providing the groove completely around the piston this pounding, with its attendant noise and vibration, is eliminated;-

and the wear of the walls of the piston groove attendant to the engagement of the operating projection with said walls is distributed around the entire piston instead of being concentrated at any one place on the walls.

To further reduce the possibilities of wear on the walls of the piston groove 14, the piston is constructed in the manner shown in Fig. 3, wherein the walls of the groove 14 in reality constitute freely rotatable thrust plates 25, 25, located in cavities 26, 26 formed in heads 27, 27, which are located at and form the opposite ends of the piston 13.

In the base of each cavity 26 is located a stationary plate 28 between which and the adj acent thrust plate is confineda series of,

anti-friction balls 29.

On the outer end of each piston head 27 is a cup washer 30, within which is located a securing plate 31.

The piston heads 27, 27 are spaced apart to form the piston groove 14 by a series of sleeves 32, 33, 32. The sleeves 32, 32 of the series are located respectively in the cavities 26, 26 between the bases thereof and the nearest of the oppositely disposed walls of the thrust plates 25, 25, which constitute the walls of the piston groove 14,the sleeve 33 being located between and overlapping the said oppositely disposed walls to maintain the groove 14.

A tie bolt 34 extends longitudinally through and from end to end of the piston 13,

passing through the securing plates 31, 31,

the cup washers 30, 30, the piston heads 27, 27, the sleeves 32, 32 and the sleeve 33, for

rigidly securing these elements together. to

form the piston 13.

' By this construction all perceptible wear on tltile walls of the piston groove 14 is eliminate To reduce the possibilities of wear on the pro ect1o n 20, this projection is formed of an elongated bar of circular and wear-resisting stock, such, for example, as hardened steel.

This bar is freely rotatably mounted between roller bearings 35, 35 which in turn are freely rotatably mounted in a bore 36 formed longitudinally of and eccentric with respect to the center of the hardened steel bearing member 10, the said bore 36 being concentrically disposed with respect to the axis of rotation of the bar or projection 20.

The relatively long bearing for the bar 20, provided by the roller bearings 35, .35, prevents relative lateral movement of the bar 20, thereby eliminating wear between the elements, which would otherwise be caused by the intermittent pressure exerted on opposite sides of this bar due to the reciprocation of the piston 13.

From the above description, it will be evident that a rolling contact is established between the operating elements which are subject to severe usage during the operation of the pump.

As shown in Fig. 2, the opposite sides of the pump casing 1 are respectively provided with fluid cavities 40 and 41, each of which extends substantially half-way around the a movement of the piston 13 in one direction therein.

As the filled end a: of the bore 12 passes the sealing sectors 42 the fluid therein is trapped in the said end of the bore 12, and as the rotor 3 continues to rotate the trapped fluid will be forced out of the said end of the bore 12 into the fluid cavity 41, and thence through the pipe 45- which communicates therewith, the piston moving toward the periphery of the rotor 3 as the rotor rotates and the piston revolves around the eccentric actuating. projection 20, and is thereby reciprocated and revolves in the bore 12 of the rotor 3.

Continued rotation of the rotor will cause this particular end of the bore 12 to pass the second sealing sector 42 for the start of a new cycle of operations, it being noted that the piston head in the opposite end of the bore 12 is working in reverse order atall times, that is when one end of the bore is under suction, the other end is under compression.

A pump made and operated as above noted is capable of being operated at relatively high speeds, for example, 1750 R. P. M., and therefore is capable of producing relatively high pressures.

This pump has been designed for use in high pressure automobiles and similar washing systems, and in actual service extending over a considerable length of time has proven eflicient, economical as to power consumption, quiet, and vibrationless, and when dis-' tendin cylindrical bore, a cylindrical piston in said cylindrical bore having an annular groove extending completely around its pcton in sa1d cylindrical bore having an am1u-' lar groove extending completely around its periphery, and an eccentric rotatably mounted projection extending from the easing into the groove in the piston, for actuating the piston when the rotor revolves.

3. A rotary pumpcomprising a casing, a rotor in said casing having a transversely extending cylindrical bore, a cylindrical piston in said cylindrical bore having an annular groove extending completely around its periphery, a pair of thrust plates rotatably mounted on said piston and respectively forming the opposed and parallel walls of said groove, and an eccentric projection extending from the casing into the groove in the piston and adapted to be engaged by said thrust plates, for actuating the piston when the rotor revolves.

4. A rotary pump comprising a casing, a rotor in said casing having a transversely extending cylindrical bore, a cylindrical piston in said cylindrical bore having an an- .nular groove extending completely around its periphery, a pair ofthrust plates rotatably mounted on said piston and respectively forming the opposed and parallel walls of said groove, and an eccentric rotatably mounted projection extending from the casing into the groove in the piston and adapted to be engaged by said thrust plates, for actuating the piston when the rotor revolves.

5. A rotary pump comprising a casing, a rotor insaid casing having a transversely extending cylindrical bore, a cylindrical plston in said cylindrical borehaving an annular.

groove extending completely around its eriphery, a pair. of thrust plates rotata lyv mounted on said piston and respectively forming the opposed and parallel wallsof prising an elongated cylin said groove, an eccentric rotatably mounted projection extending from the easing into the groove in the plston and adapted to be engaged by said thrust plates, for actuatingthe piston when the rotor revolves, and antifriction bearings for said rotatable thrust plates and said rotatable projection.

6. A rotary pump comprising a casing, a rotor in said casing having a transversely extending cylindrical bore, a cylindrical piston in said cylindrical-bore having an annular groove extending completely around its periphery, and an eccentric rojection com- 7 ical bar rotatably mounted in one end of said casing and extending from the easing into the groove in the piston, for-actuating the piston when the rotor revolves.

" tata actuating the piston when the rotor revolves.

8. A rotary pump comprising a casing, a rotor in said casing having a counterbore formed in one ofits ends and a transversely extending cylindrical bore intermediate its respective ends, a bearing member extending from one end of the casing into said counterbore, -a cylindrical piston in said cylindrical bore having an annular groove extending completely around its periphery, and an eccentric projection extending from the casing bearing member into the groove in the piston, for actuating the piston when the rotor revolves.

9. A rotary pump comprising a casing, a rotor in said casing having a counterbore formed in one of its ends and a transversely ton, for actuating the piston when the rotor revolves.

OLAF s. JOHNSON. 

